Using the BayStack 450 10/100/1000 Series Switch1-30 302401-D Rev 00• You can downline upgrade the entire stack from any switch in the stack.• You can access and manage the stack using a TELNET connection or anygeneric SNMP management tool through any switch port that is part of thestack configuration.• When stacking three or more switches, use the longer (1-meter) cascademax-return cable (PN 303979-A) to complete the link from the last unit in thestack to the base unit.Redundant Cascade Stacking FeatureBayStack 450 switches allow you to connect up to 8 units into a redundantcascade stack. If any single unit fails or if a cable is accidently disconnected, otherunits in the stack remain operational, without interruption.Figure 1-14 shows an example of how a stack configuration reacts to a failed orpowered-down unit in the stack configuration:1. As shown in Figure 1-14, unit 3 becomes nonoperational.This can be the result of a failed unit, or simply because the unit was powereddown.2. Unit 2 and unit 4, directly upstream and downstream from unit 3, sense theloss of link signals from unit 3.a. Units 2 and 4 automatically loop their internal stack signals (A and B).b. The Cas Up LED for unit 2 and the Cas Dwn LED for unit 4 turn on(amber) to indicate that the stack signals are looped.3. The remaining stack units remain connected.Although the example shown in Figure 1-14 shows a failed unit causing the stackto loop signals at the points of failure (A and B), the system reacts the same way ifa cable is removed.kombk.book Page 30 Tuesday, June 29, 1999 3:25 PM
